For electrical connection between electric wires or between an electric wire and an electric device to transmit electrical signals, a connector is used. FIG. 9 is a longitudinal sectional view showing a conventional example of such a connector. This connector prevents a terminal fitting 70 which has been inserted into a housing 75 from falling off, by double locking operation using a lance 71 and a retainer 72 (Reference should be made to Patent Document 1, for example).
Specifically, this connector is so constructed that the terminal fitting 70 is formed with a square cylindrical part 73 in a columnar shape, and two locking parts 74 are provided at a rear end edge of the square cylindrical part 73 in parallel with each other in a lateral direction. When the lance 71 and the retainer 72 are arranged in parallel in the lateral direction in the housing 75, the lance 71 is locked to one of the two locking parts 74, and the retainer 72 is locked to the other locking part 74.
Therefore, in this connector, in order to assemble the terminal fitting 70 to the housing 75, the retainer 72 is held in a temporarily locked position, as a first step, and a retaining part 76 is kept retreated out of an insertion passage of the terminal fitting 70. In this state, the terminal fitting 70 is inserted into a cavity 77 from a back side. In a process of this insertion, the terminal fitting 70 and the retainer 72 are held in a non contact state. However, because a front end edge of a support plate 79 of the square cylindrical part 73 is butted against a retaining projection 78 of the lance 71, the lance 71 is retreated out of the insertion passage of the terminal fitting 70, and at the same time, the retaining projection 78 comes into sliding contact with an outer face of the support plate 79. When the lance 71 is bent, a circular face of the support plate 79 is brought into contact with the retaining projection 78, and hence, the lance 71 can be smoothly bent without being caught.
When the terminal fitting 70 has been inserted up to a normal position, the square cylindrical part 73 passes over the retaining projection 78, and the retaining projection 78 is disengaged from the support plate 79 thereby to elastically restore the lance 71. With this elastic restoration of the lance 71, a locking face 78A of the retaining projection 78 is locked to the locking part 74 at the right side of the square cylindrical part 73 from the back side, into a primary locked state. Thereafter, when the retainer 72 which is on standby at the temporarily locked position is pushed upward in a diagonally forward direction, the retainer 72 slides to a normally locked position, and a locking face 76A of the retaining part 76 is locked to the locking part 74 at the left side of the square cylindrical part 73 from the back side, into a secondary locked state. In this manner, the terminal fitting 70 is double locked with the lance 71 and the retainer 72, and reliably held so as not to fall off.
According to this structure, a shape of the terminal fitting 70 can be simplified, because the rear end edge of the square cylindrical part 73 of the terminal fitting 70 serves both as locking means with respect to the lance 71 and locking means with respect to the retainer 72. Moreover, according to this structure, the terminal fitting 70 fitted to a cable 80 will not be inclined to the right or left inside the housing 75, and further, can be locked and held so as not to easily fall off.